JP4911112B2 - Engine control device - Google Patents

Description

  The present invention relates to an engine control device, and more specifically to a technique for controlling an engine in accordance with required values from a plurality of control systems mounted on a vehicle.

  The vehicle is equipped with a plurality of control systems such as an automatic transmission and cruise control. The engine is controlled according to a required value output from each control system. For example, in order to realize a driving force according to the accelerator opening, the engine is controlled to realize a required torque value. Further, in order to reduce a shift shock or the like, the engine is controlled so as to realize a required value of the retard amount of the ignition timing during the shift of the automatic transmission. Further, in order to keep the vehicle speed constant, the engine is controlled so as to realize the required value of the throttle opening. The engine control system arbitrates a request value requested from another control system, and controls the engine according to the request value selected as a result of the arbitration.

  However, if the required values required from each control system are not unified, the required values cannot be arbitrated correctly. For example, since the throttle opening and the ignition timing have different dimensions, it is impossible to determine which request value should be realized with priority. Therefore, a technique for unifying torque required values from each control system has been proposed.

For example, Japanese Patent Application Laid-Open No. 2007-198157 (Patent Document 1) discloses an engine control device that performs torque-based engine control. According to this, torque control in torque-based engine control includes low response torque control by intake air amount operation represented by electric throttle operation, and intake air amount operation represented by ignition retard and fuel cut. In response to the two types of high response torque control performed without the control, two types of target torques of low response target torque and high response target torque are set for each torque control method. The engine control device includes estimated torque calculation means for estimating the actually generated engine torque when the low response torque control is performed, and the high response torque is calculated so as to eliminate the difference between the estimated engine torque estimated value and the target torque. Control is implemented.
JP 2007-198157 A

  Here, in the engine control apparatus of Patent Document 1, the estimated torque calculation means for estimating the actually generated engine torque has a transient response physical model related to the intake and exhaust system parts of the engine, and is calculated by the transient response physical model. Conversion to the engine torque estimated value is performed based on the obtained intake pipe pressure information. Then, the estimated torque calculation means performs normalization processing so that the estimated engine torque value becomes 1 in a steady state, and integrates the normalized engine torque estimated value and the target engine torque to obtain the final engine torque. Calculate an estimate. Thereby, according to the engine control apparatus of patent document 1, an engine torque can be estimated with high precision. However, on the other hand, since complicated calculation processing is required for calculation of the estimated engine torque value, there is a problem that a large calculation load is applied to the engine control device. Therefore, in the engine control apparatus of Patent Document 1, if high-speed arithmetic processing is to be realized, the cost and the physique are increased.

  Therefore, the present invention has been made to solve such a problem, and an object of the present invention is to provide an engine control device that can suitably realize a demand for the engine with a simple control structure. .

  According to an aspect of the present invention, the engine control device is controlled in accordance with request values required from a plurality of control systems. The engine is provided with a plurality of actuators that adjust the output of the engine in accordance with the operation amount. The plurality of control systems includes a first control system that requests a convergence destination request value to be converged from the engine based on the driving state of the vehicle, and a unit for the engine based on the driving state of the vehicle. And a second control system that requests an instantaneous required value to be satisfied every time. The control device converts the requested convergence destination value into a first parameter that is selected in advance from a plurality of parameters representing the operating state of the engine and that is commonly controlled by a plurality of actuators. Means for estimating an instantaneous target value of the first parameter to be satisfied per unit time in order to converge to the convergence target value of the first parameter based on the response time constant of the first parameter; The second conversion means for converting the instantaneous required value from the second control system into the instantaneous target value of the first parameter, and the instantaneous target value of the first parameter converted by the first conversion means, The target value reflecting means for reflecting the instantaneous target value of the first parameter converted by the converting means, and the operation of the plurality of actuators according to the instantaneous target value reflected by the target value reflecting means. And a drive control means for controlling the amount.

  Preferably, the target value reflecting means arbitrates the instantaneous target value of the first parameter converted by the first converting means and the instantaneous target value of the first parameter converted by the second converting means. Based on the result, the instantaneous target value of the first parameter is calculated.

  Preferably, the target value reflecting means adds the instantaneous target value of the first parameter converted by the first converting means and the instantaneous target value of the first parameter converted by the second converting means.

  Preferably, the plurality of actuators constitute an intake mechanism including a throttle valve. The first conversion means converts the convergence destination required value into the charging efficiency of the engine.

  Preferably, the plurality of actuators include a throttle valve, a spark plug, and an injector. The first conversion means converts the convergence destination required value into engine power or torque.

  Preferably, the first control system includes means for calculating a convergence destination required value based on an accelerator pedal operation amount by a driver. The second control system includes means for calculating an instantaneous required value based on a cruise control function that keeps the vehicle speed instructed by the driver constant.

  According to the present invention, a demand for an engine can be suitably realized with a simple control structure.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

  FIG. 1 is a schematic block diagram showing a power train of a vehicle equipped with an engine control apparatus according to an embodiment of the present invention. In the present embodiment, the automatic transmission will be described as having a gear-type transmission mechanism including a torque converter as a fluid coupling. Note that the present invention is not limited to an automatic transmission having a gear-type transmission mechanism, and may be a continuously variable transmission such as a belt type. The gear-type speed change mechanism may be constituted by a planetary gear or may be constituted by a constantly meshing gear.

  Referring to FIG. 1, the power train of a vehicle includes an engine 100, a torque converter 200, an automatic transmission 300, and an ECU (Electronic Control Unit) 1000.

  The amount of air taken into engine 100 is adjusted by throttle valve 102. In addition, a variable intake system is provided to effectively use the pulsation effect caused by pressure pulsation generated in the intake air and to increase the torque of the engine 100.

  In the variable intake system, an ACIS (Acoustic Control Induction System) valve 104 switches the effective intake pipe length in two stages in accordance with the period of the pulsating flow. The opening and closing of the ACIS valve 104 is controlled according to the throttle opening and the target torque.

  For example, when the throttle opening or the target torque is large and the load is high, the ACIS valve 104 is controlled so that the effective intake pipe length becomes long. On the other hand, when the throttle opening or the target torque is small and the load is low, the ACIS valve 104 is controlled so that the effective intake pipe length is shortened.

  Further, the amount of air charged in the cylinder of engine 100, that is, the output torque of engine 100, is adjusted by changing the opening / closing timing of intake valve 108 and exhaust valve 110 by variable valve timing mechanism 106. The opening / closing timing of the intake valve 108 and the exhaust valve 110 is controlled according to the throttle opening.

  For example, the cylinder is filled by adjusting the overlap amount between the intake valve 108 and the exhaust valve 110 according to the throttle opening, that is, according to the load, or adjusting the closing timing of the intake valve 108. The amount of air, internal EGR (Engine Gas Recirculation), and the like are adjusted, and the output torque of engine 100 is finely controlled.

  The output shaft of engine 100 is connected to the input shaft of torque converter 200. Engine 100 and torque converter 200 are connected by a rotating shaft. Therefore, output shaft rotational speed NE (engine rotational speed NE) of engine 100 detected by the engine rotational speed sensor and input shaft rotational speed (pump rotational speed) of torque converter 200 are the same.

  The torque converter 200 includes a lock-up clutch that directly connects an input shaft and an output shaft, a pump impeller on the input shaft side, a turbine impeller on the output shaft side, a stator that has a one-way clutch and expresses a torque amplification function, Consists of Torque converter 200 and automatic transmission 300 are connected by a rotating shaft. The output shaft rotational speed NT (turbine rotational speed NT) of the torque converter 200 is detected by a turbine rotational speed sensor. The output shaft rotational speed NOUT of the automatic transmission 300 is detected by an output shaft rotational speed sensor.

  Such an automatic transmission 300 includes a plurality of friction elements such as clutches and brakes. Based on a predetermined operation table, the hydraulic circuit is controlled so that a clutch element, a brake element, and a one-way clutch element, which are friction elements, are engaged and released corresponding to each requested gear stage. . Shift positions (shift positions) of the automatic transmission 300 include a parking (P) position, a reverse travel (R) position, a neutral (N) position, and a forward travel (D) position.

  The ECU 1000 that controls these power trains includes an engine ECU 1010 that controls the engine 100 and an ECT (Electronic Controlled Transmission) _ECU 1020 that controls the automatic transmission 300.

  In the present embodiment, ECU 1000 calculates a required torque as a target torque of engine 100 based on the engine speed, the accelerator opening, and the like, and throttle valve 102 of engine 100 so as to realize the calculated required torque. To control.

  Based on the required torque calculated by the ECU 1000, the engine ECU 1010 of the ECU 1000 calculates the required throttle opening as the target opening of the throttle valve 102, and controls the throttle valve 102 so that the throttle opening becomes the required throttle opening. .

  Here, in addition to the control system that controls the engine 100 so as to realize the required torque according to the accelerator opening, the vehicle is equipped with various control systems. It is controlled according to the required value output from each of the systems. The plurality of control systems include, for example, control systems such as an automatic transmission 300, cruise control, VSC (Vehicle Stability Control), and TRC (TRaction Control).

  Cruise control is control that keeps the vehicle speed constant. VSC is a control that ensures the safety of the vehicle by automatically setting the brake hydraulic pressure of each wheel and the target driving force of the vehicle when the sensor detects a state where the front and rear wheels are likely to skid. The TRC automatically sets the brake hydraulic pressure of each wheel, the target driving force of the vehicle, etc., when the sensor detects idling of the driving wheel when starting and accelerating on a slippery road surface to ensure the optimum driving force. Control.

  Here, the required values output from the plurality of control systems to the engine 100 include torque, throttle opening, ignition timing, power, and the like, and their types are not unified. In the present embodiment, the engine ECU 1010 requests the engine 100 from each control system because the request values cannot be properly adjusted unless the types of request values required from each control system are unified. The required value is converted into a torque required value.

  Engine ECU 1010 calculates the requested throttle opening based on the requested value from each control system converted into torque. At this time, the required throttle opening is calculated based on the required torque that reflects the required value from another control system with respect to the required torque corresponding to the accelerator opening, by a method described later.

  ECT_ECU 1020 receives a signal representing output shaft rotational speed NOUT detected by the output shaft rotational speed sensor. ECT_ECU 1020 receives an engine speed signal representing engine speed NE detected by the engine speed sensor from engine ECU 1010.

  These rotational speed sensors are provided to face teeth of a rotation detection gear attached to the input shaft of the torque converter 200, the output shaft of the torque converter 200, and the output shaft of the automatic transmission 300. These rotational speed sensors are sensors that can detect slight rotations on the input shaft of the torque converter 200, the output shaft of the torque converter 200, and the output shaft of the automatic transmission 300. For example, they are generally referred to as semiconductor sensors. This is a sensor using a magnetoresistive element.

  ECT_ECU 1020 outputs a lockup clutch control signal for torque converter 200. Based on this lockup clutch control signal, the engagement pressure of the lockup clutch is controlled. The ECT_ECU 1020 outputs a solenoid control signal to the automatic transmission 300. Based on this solenoid control signal, the linear solenoid valve, the on-off solenoid valve, etc. of the hydraulic circuit of the automatic transmission 300 are controlled, and friction is established so as to constitute a predetermined shift gear stage (for example, first speed to fifth speed). The engagement element is controlled to be engaged and released.

  The ECT_ECU 1020 is supplied with a signal representing the opening (accelerator opening) of the accelerator pedal 2102 operated by the driver from the accelerator opening sensor 2100 and a signal representing the vehicle speed from the vehicle speed sensor 2200. The ECT_ECU 1020 detects the change rate of the accelerator opening based on the signal transmitted from the accelerator opening sensor 2100. ECU 1000 has a memory in which various data and programs are stored. In addition, instead of the accelerator opening, the depression force of the accelerator pedal 2102 may be detected. Similarly, instead of the change rate of the accelerator opening, the change rate of the depression force of the accelerator pedal 2102 may be detected. A signal representing the accelerator opening is also input to engine ECU 1010.

  Engine ECU 1010 and ECT_ECU 1020 transmit and receive signals to and from each other. In the present embodiment, engine ECU 1010 calculates an actual net engine torque used for controlling automatic transmission 300 and transmits it to ECT_ECU 1020. The ECT_ECU 1020 controls the automatic transmission 300 using the actual net engine torque transmitted from the engine ECU 1010.

  FIG. 2 is a block diagram showing a control structure of the engine control apparatus according to the present embodiment. Each function block shown in FIG. 2 is typically realized by the engine ECU 1010 executing a program stored in advance, but part or all of the function may be implemented as dedicated hardware.

  Referring to FIG. 2, engine ECU 1010 includes required torque calculation unit 1110, required value conversion unit 1120, instantaneous required value estimation unit 1130, instantaneous required torque calculation unit 1140, instantaneous required value conversion unit 1150, and addition. Unit 1160 and instantaneous required throttle opening degree calculation unit 1170.

  The throttle valve 102 is an electric motor controlled throttle valve that is driven by a motor, and its opening degree is controlled by the opening degree control unit 120. The opening degree control unit 120 includes a drive unit 122 that drives the motor and an opening degree detection unit (not shown).

When the drive unit 122 receives a signal indicating the instantaneous required throttle opening degree TA ^* (t) from the instantaneous required throttle opening degree calculation unit 1170, the actual throttle opening detected by the opening degree detection unit is the required throttle opening degree TA ^*. The throttle valve 102 is controlled so as to coincide with (t).

Requested torque calculation unit 1110 receives a signal indicating accelerator opening ACC from accelerator opening sensor 2100, and receives a signal indicating engine speed NE from engine speed sensor 130. The accelerator opening ACC and the engine speed NE are included in the information related to the driving state of the vehicle. Required torque calculation unit 1110 calculates required torque of engine 100 (target torque of engine 100) TR ^* based on these signals. It should be noted that required torque TR ^* of engine 100 is calculated based on a map obtained in advance, for example, through experiments.

The required value conversion unit 1120 converts the required torque TR ^* calculated by the required torque calculation unit 1110 into a parameter to be controlled. The parameter to be controlled is a parameter controlled in order to achieve the required torque TR ^* , and a plurality of actuators that adjust the output of the engine 100 are selected from a plurality of parameters representing the operating state of the engine 100. A common parameter is selected.

  Specifically, the amount of air charged in the cylinders of engine 100 (air filling amount) has a high correlation with the output torque of engine 100. As described above, the air filling amount is adjusted by controlling a plurality of actuators such as the throttle valve 102, the ACIS valve 104, and the variable valve timing mechanism 106 (the intake valve 108 and the exhaust valve 110). That is, the plurality of actuators constitute an intake mechanism for adjusting the amount of air taken into engine 100. In addition to the above-described valves, the plurality of actuators include a supercharger and the like.

Request value conversion unit 1120 selects charging efficiency KL as a parameter common to the plurality of actuators constituting the intake mechanism of engine 100. The charging efficiency KL is a ratio between the amount of air actually sucked into the cylinder and the amount of air that should theoretically be sucked, and can be calculated from the engine speed NE and the amount of intake air. Then, required value conversion unit 1120 converts required torque TR ^* of engine 100 into required charging efficiency KL ^* that is a target value of charging efficiency KL of engine 100. The conversion from the required torque TR ^* to the required charging efficiency KL ^* is performed based on, for example, a map determined in advance by experiments or the like.

Upon receiving the required filling efficiency KL ^* from the required value conversion unit 1120, the instantaneous required value estimation unit 1130 receives the instantaneous charge that should be satisfied every predetermined unit time T until the actual filling efficiency KL converges to the required filling efficiency KL ^*. Estimate the required filling efficiency kl_t ^* (t). This unit time T is set in advance so as to correspond to the control cycle of engine ECU 1010, for example.

  In the present embodiment, the requested value (requested torque) that should be converged by engine 100 after the time when the request from the vehicle driver (the amount of operation of accelerator pedal 2102) is issued is the “convergence destination requested value”. Called. On the other hand, a request value that should be satisfied by engine 100 instantaneously (per unit time T) with respect to the convergence destination request value is referred to as an “instantaneous request value”. That is, the required response is different between the convergence destination required value and the instantaneous required value, and the instantaneous required value is required to have a higher response than the convergence destination required value. In the present embodiment, the required value (requested torque) calculated in response to the driver's request mainly corresponds to the convergence destination required value, and in the control system such as the automatic transmission 300, cruise control, VSC, TRC, the vehicle The required value that is automatically set according to the behavior of the key corresponds mainly to the instantaneous required value.

Here, the instantaneous required charging efficiency kl_t ^* (t) is estimated by the response time constant of the charging efficiency (actual charging efficiency) KL of the air sucked into the actual cylinder by the plurality of actuators constituting the intake mechanism of the engine 100. Based on.

Specifically, when required torque TR ^* is calculated based on accelerator opening ACC, engine ECU 1010 calculates and opens an actuator command value (for example, required throttle opening) according to required torque TR ^*. Output to the degree control unit 120. However, there is a response delay until the change in the required torque TR ^* actually appears as a change in the output torque, and the response time depends on the change in the engine operating range such as the engine speed NE and the load, and the intake pipe pressure It changes under the influence of the intake air flow velocity. This response delay has a characteristic that it increases as the engine speed NE decreases. For this reason, in the low engine speed range, the difference between the required torque TR ^* and the actual torque becomes large, and a phenomenon may occur in which the engine speed NE temporarily drops.

Therefore, the instantaneous required value estimation unit 1130 estimates the instantaneous required charging efficiency kl_t ^* (t) to be satisfied for each unit time T based on the response time constant of the charging efficiency KL. Specifically, the instantaneous required value estimation unit 1130 acquires in advance an experiment or the like the relationship between the charging efficiency kl (t + T) and the engine speed NE when the unit time T has elapsed from the present time. FIG. 3 shows the relationship between the charging efficiency kl (t + T) and the engine speed NE when the unit time T has elapsed from the current time when the current charging efficiency kl (t) is a predetermined value (x%). Indicated. The instantaneous required value estimation unit 1130 has the relationship shown in FIG. 3 in advance as a map. When the engine speed NE is received from the engine speed sensor 130, the instantaneous required value estimation unit 1130 acquires the current charging efficiency kl (t) and With reference to the map, the charging efficiency kl (t + T) at the time when the unit time T has elapsed from the present time is estimated based on the engine speed NE. Then, the instantaneous required value estimation unit 1130 sets the estimated charging efficiency kl (t + T) to the instantaneous required charging efficiency kl_t ^* (t) that the engine 100 should satisfy when the unit time T has elapsed from the present time.

  As described above, according to the present embodiment, the convergence target required value is converted into the instantaneous required value based on the response characteristics of the plurality of actuators, so that the same responsiveness as the required torque is always obtained regardless of the engine speed NE. Torque is output. As a result, even in the low engine speed range, the difference between the required torque and the actual torque becomes small, and the drop in the engine speed NE can be suppressed.

Furthermore, as will be described below, it is possible to easily reflect a required value required for engine 100 from another control system to required torque TR ^* . As a result, the demand for engine 100 can be more suitably realized with a simple control structure.

Specifically, referring to FIG. 2, instantaneous required torque calculation unit 1140 receives a required value from control system 1030. The control system 1030 includes control systems such as an automatic transmission 300, cruise control, VSC, and TRC (TRaction Control). The instantaneous required torque calculation unit 1140 receives a required value of the throttle opening TA, for example, from cruise control. The instantaneous required torque calculation unit 1140 converts the received required value of the throttle opening TA into torque. At this time, the instantaneous required torque calculation unit 1140 converts the required value of the throttle opening TA into the instantaneous required torque tr ^* (t) according to a predetermined map.

Instantaneous required value conversion unit 1150 further converts instantaneous required torque tr ^* (t) into instantaneous required charging efficiency kl_c ^* (t), which is an instantaneous target value of charging efficiency KL of engine 100. Note that the conversion from the instantaneous required torque tr ^* (t) to the instantaneous required charging efficiency kl_c ^* (t) is performed based on, for example, a map determined in advance by experiments or the like.

Addition section 1160, the instantaneous demand charging efficiency Kl_t ^* received the (t) from the instantaneous requirement value estimating unit 1130, when receiving the instantaneous requested charging efficiency Kl_c ^* (t) from the instantaneous demand value converting unit 1150, by adding these The instantaneous required filling efficiency kl ^* (t), which is the final target value, is calculated.

The instantaneous required throttle opening calculation unit 1170 calculates an instantaneous required throttle opening TA ^* (t) as an instantaneous target opening based on the calculated instantaneous required filling efficiency kl ^* (t). The instantaneous required throttle opening degree TA ^* (t) is calculated using a map obtained in advance by experiments or the like.

When the drive unit 122 receives the instantaneous required throttle opening degree TA ^* (t), the actual throttle opening degree TA (t) detected by the opening degree detection unit matches the required throttle opening degree TA ^* (t). The throttle valve 102 is controlled.

  Regarding the correspondence between the control structure of the engine ECU 1010 shown in FIG. 2 and the present invention, the required torque calculation unit 1110 corresponds to a “first control system” and the control system 1030 corresponds to a “second control system”. . Further, the required value conversion unit 1120 and the instantaneous required value estimation unit 1130 correspond to “first conversion means” and “estimation means”, respectively. Furthermore, the instantaneous required torque calculation unit 1140 and the instantaneous required value conversion unit 1150 correspond to a “second conversion unit”, and the addition unit 1160 corresponds to a “target value reflection unit”.

In the control structure shown in FIG. 2, as a means to reflect the requested value from the other control system to the request torque TR ^*, the required value of the required torque TR ^* and other control systems each instant Although it was set as the structure which converts and adds to required filling efficiency kl_t ^* (t), kl_c ^* (t), as a structure which selects either one of instantaneous required filling efficiency according to the priority order predetermined between control systems. Also good. Moreover, it is good also as a structure which calculates the intermediate value of two instantaneous required filling efficiency. That is, the instantaneous required filling efficiency kl_t ^* (t) and the instantaneous required filling efficiency kl_c ^* (t) may be adjusted.

The required value conversion unit 1120 is configured to convert the required torque TR ^* and the required value from the control system 1030 into the charging efficiency KL that is a parameter common to the intake mechanism including the throttle valve 102. It is also possible to convert the value into power (or torque) that is a parameter common to a plurality of actuators including the throttle valve 102, an injector, and a spark plug (both not shown).

The power of engine 100 is a physical quantity calculated as the product of torque and engine speed. In this case, the required torque TR ^* and the required value from the control system 1030 are converted to the instantaneous required power, and then adjusted to the instantaneous required power that is the final target value. Then, the combustion injection amount from the injector, the ignition timing by the spark plug, and the throttle opening are controlled according to the converted instantaneous required power.

  FIG. 4 is a flowchart for illustrating a control structure of a program executed by the engine control apparatus according to the present embodiment. Note that the program shown in FIG. 4 is repeatedly executed in a predetermined control cycle (corresponding to the unit time T).

Referring to FIG. 4, when the process is started, engine ECU 1010 acquires engine speed NE and accelerator opening ACC. Then, engine ECU 1010 calculates required torque TR ^* based on the acquired engine speed NE and accelerator opening ACC (step S01).

Next, engine ECU 1010 converts calculated required torque TR ^* into a target value (required charging efficiency KL ^* ) of charging efficiency KL, which is a parameter common to a plurality of actuators constituting the intake mechanism of engine 100 (step S02).

Further, engine ECU 1010 estimates instantaneous required charging efficiency kl_t ^* (t) per unit time T based on the response time constant of charging efficiency KL when the intake mechanism including throttle valve 102 is operated (step S03). .

Next, engine ECU 1010 converts a required value from a control system such as automatic transmission 300 and cruise control into instantaneous required torque tr ^* (t). Then, the converted instantaneous required torque tr ^* (t) is further converted into the instantaneous required charging efficiency kl_c ^* (t) for each unit time T (step S04).

Finally, the engine ECU 1010 adds the instantaneous required charging efficiency kl_t ^* (t) and kl_c ^* (t) acquired in steps S03 and S04, respectively, so that the instantaneous required charging efficiency kl that the engine 100 should finally satisfy is added. ^* (T) is calculated (step S05). Then, engine ECU 1010 calculates instantaneous required throttle opening degree TA ^* (t) based on the calculated instantaneous required filling efficiency kl ^* (t) (step S06). When receiving the instantaneous required throttle opening degree TA ^* (t) from engine ECU 1010, drive unit 122 controls throttle valve 102 so that actual throttle opening degree TA (t) becomes the required throttle opening degree TA ^* (t). To do.

Finally, the effects of the engine control apparatus according to the embodiment of the present invention will be described in detail with reference to FIGS. FIG. 5 shows the engine output (torque) when the engine 100 is controlled only according to the required torque TR ^* (that is, the convergence destination required value) calculated based on the accelerator opening for comparison. . On the other hand, FIG. 6 shows engine output (torque) controlled by the engine control apparatus according to the present embodiment.

Referring to FIG. 5, in the conventional control structure, when required torque TR ^* is calculated in response to a request from the driver (the amount of operation of accelerator pedal 2102) at time t1, the calculated required torque TR ^* is calculated ^. Based on the above, a required throttle opening degree TA ^* which is a convergence destination required value is calculated. Upon receiving the calculated required throttle opening degree TA ^* , the driving unit 122 controls the throttle valve 102 so that the actual throttle opening degree coincides with the required throttle opening degree TA ^* . Thereby, as shown in FIG. 5, the throttle opening degree TA converges to the required throttle opening degree TA ^* at time t2 after time t1. At this time, the engine output also converges to the required output (required torque TR ^* ) at time t2.

However, in the control structure shown in FIG. 5, during the period from time t1 to time t2, the response times of the plurality of actuators constituting the intake mechanism of engine 100 depend on the engine operating range such as engine speed NE and load. As a result, the engine output also changes with the change in the engine operating range. That is, during the period, the instantaneous required torque tr ^* required from the control system such as the automatic transmission 300 and the cruise control cannot be satisfied, which may cause a problem that the stability of the vehicle cannot be ensured.

On the other hand, in the present embodiment, as shown in FIG. 6, when the required torque TR ^* is calculated in response to a request from the driver at time t1, the calculated required torque TR ^* is used as the intake mechanism. Are converted into instantaneous required values for each unit time T in consideration of response characteristics of a plurality of actuators constituting the. Then, the instantaneous required torque tr ^* required from the control system such as the automatic transmission 300 and the cruise control is added to the converted instantaneous required value.

As a result, the throttle opening degree TA is controlled according to the instantaneous required throttle opening degree TA ^* (t) set for each unit time T. As a result, the engine output converges to the required output (requested torque) at time t2 while satisfying the instantaneous required torque per unit time T.

  As described above, the engine control device according to the present embodiment converts the convergence destination required value into an instantaneous required value considering the responsiveness of a plurality of actuators, and thereby the vehicle behavior with respect to the convergence destination required value. It is possible to easily reflect the instantaneous required value that is automatically set according to the above. As a result, it is possible to suitably respond to requests from a plurality of control systems having different responsiveness.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is a schematic block diagram showing a power train of a vehicle equipped with an engine control device according to an embodiment of the present invention. It is a block diagram which shows the control structure of the control apparatus of the engine which concerns on embodiment of this invention. It is a figure which shows the relationship between the response time constant of engine filling efficiency, and an engine speed. It is a flowchart for demonstrating the control structure of the program which the engine control apparatus which concerns on embodiment of this invention performs. It is a figure for demonstrating the engine output characteristic controlled by the conventional engine control apparatus. It is a figure for demonstrating the engine output characteristic controlled by the control apparatus of the engine which concerns on embodiment of this invention.

Explanation of symbols

  100 engine, 102 throttle valve, 104 ACIS valve, 106 variable valve timing mechanism, 108 intake valve, 110 exhaust valve, 120 opening control unit, 122 drive unit, 130 engine speed sensor, 200 torque converter, 300 automatic transmission, 1010 engine ECU, 1030 control system, 1110 required torque calculation unit, 1120 required value conversion unit, 1130 instantaneous required value estimation unit, 1140 instantaneous required torque calculation unit, 1150 instantaneous required value conversion unit, 1160 addition unit, 1170 instantaneous request throttle open Degree calculation unit, 2100 accelerator opening sensor, 2102 accelerator pedal, 2200 vehicle speed sensor.

Claims (6)

An engine control device controlled in accordance with request values required from a plurality of control systems,
The engine is provided with a plurality of actuators that adjust the output of the engine according to the operation amount,
The plurality of control systems include:
A first control system that requests a convergence destination request value to be converged with respect to the engine based on a driving state of the vehicle;
A second control system that requests an instantaneous required value to be satisfied per unit time from the engine based on the driving state of the vehicle,
The controller is
First conversion means for converting the convergence destination required value into a first parameter that is selected in advance from among a plurality of parameters representing the operating state of the engine and that is commonly controlled by the plurality of actuators. When,
Estimating means for estimating an instantaneous target value of the first parameter that should be satisfied for each unit time in order to converge to a convergence target value of the first parameter based on a response time constant of the first parameter; ,
Second conversion means for converting the instantaneous required value from the second control system into an instantaneous target value of the first parameter;
Target value reflecting means for reflecting the instantaneous target value of the first parameter converted by the second converting means to the instantaneous target value of the first parameter converted by the first converting means;
An engine control apparatus comprising: drive control means for controlling the operation amounts of the plurality of actuators according to the instantaneous target value reflected by the target value reflecting means.   The target value reflecting means adjusts the instantaneous target value of the first parameter converted by the first converting means and the instantaneous target value of the first parameter converted by the second converting means. The engine control device according to claim 1, wherein an instantaneous target value of the first parameter is calculated based on the result obtained.   The target value reflecting means adds the instantaneous target value of the first parameter converted by the first converting means and the instantaneous target value of the first parameter converted by the second converting means. The engine control device according to claim 2. The plurality of actuators constitute an intake mechanism including a throttle valve,
The engine control device according to claim 1, wherein the first conversion unit converts the convergence destination required value into a charging efficiency of the engine. The plurality of actuators include a throttle valve, a spark plug, and an injector,
The engine control device according to any one of claims 1 to 3, wherein the first conversion means converts the convergence destination required value into power or torque of the engine. The first control system includes means for calculating the convergence destination required value based on an accelerator pedal operation amount by a driver,
The said 2nd control system contains the means for calculating the said instantaneous request value based on the cruise control function which keeps the vehicle speed instruct | indicated by the said driver constant. Engine control device.

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